Centrifugal Pump and Series of Centrifugal Pumps

ABSTRACT

A centrifugal pump having a pump housing, a bearing support assembly connected to the pump housing, a housing cover between the pump housing and the bearing support assembly, a rotationally drivable shaft supported in the bearing support assembly. The shaft extends into the pump housing through the bearing support assembly and the housing cover, coaxially to an axis of rotation. The pump further includes an impeller arranged in the pump housing and fastened to the shaft. At least two of the pump housing, housing cover, bearing support assembly, drivable shaft and impeller are configured in conformance with at least two standards, such that interface areas that are not defined by the standards between pairs of the pump components are geometrically identical. The invention further relates to a series of centrifugal pumps using such a centrifugal pump.

This application is a National Stage of PCT International ApplicationNo. PCT/EP2013/0523374, filed Feb. 7, 2013, which claims priority under35 U.S.C. §119 from German Patent Application No. 10 10 2012 002 325.1,filed Feb. 8, 2012, and German Patent Application No. 10 2013 201 902.5,filed Feb. 6, 2013, the entire disclosures of which are expresslyincorporated by reference herein.

BACKGROUND AND SUMMARY OF THE INVENTION

The invention relates to a centrifugal pump, in which at least one pumpcasing, a bearing support assembly connected directly or indirectly tothe pump casing, a casing cover arranged between the pump casing and thebearing support assembly, a rotationally drivable shaft which issupported in the bearing support assembly and which extends into thepump casing through the bearing support assembly and casing covercoaxially with respect to an axis of rotation, and an impeller arrangedin the pump casing and fastened on the shaft are provided as components.The invention also relates to a series of centrifugal pumps using such acentrifugal pump.

Centrifugal pumps per se are widespread and are used in many sectors toconvey fluids.

German patent publication no. DE 23 27 262 A discloses an apparatus inorder to provide selectively fixedly and detachably coupled centrifugalpumps composed of exchangeable building block parts which have aplurality of different exchangeable casings with in each case anidentical rear opening. The apparatus furthermore comprises a pluralityof different exchangeable impellers, each of which can be accommodatedin each of the casings, a plurality of different exchangeable driveshafts, each of which can be accommodated in each of the casings and canbe effectively connected therein to each of the impellers, a pluralityof different exchangeable connecting pieces, each of which has anidentical connecting means at one end in order to enable that each givenconnecting piece can be connected to the rear end of each of thecasings. The apparatus furthermore comprises different exchangeabledrive means, each of which can be connected to each of the connectingpieces and each of the pump drive shafts for driving the pump, anddifferent exchangeable seals which with a selected connecting pieceserve to seal the rear opening of the selected casing, wherein at leastone connecting piece and an assigned seal can be connected between aselected casing and a selected drive in order to form the desiredfixedly coupled centrifugal pump, and wherein at least one otherconnecting piece and an assigned seal, instead of the first statedconnecting piece and the assigned seal, can optionally and alternatelybe connected for attachment between a selected casing and a selecteddrive in order to form a detachably coupled centrifugal pump.

Different standards apply depending on the sectors of industry in whichthe pumps are operated. The international water standard EN 733 andchemical standard ISO 2858 should be mentioned here by way of example.Since these standards provide among other things different geometriesfor certain components, in each case separate forms of the pumps havebeen produced over time for the different applications. This leads to alarge variety of components with the associated disadvantages and thusultimately to higher manufacturing costs.

The object of the invention lies in further reducing the number ofdifferent components required for the manufacture of centrifugal pumpswhich correspond in particular to a standard.

The object is achieved according to the invention in that at least twoof the components are defined at least in two standards, whereininterface areas, which are not taken into account in the standards, of aplurality of the components that are defined in the standards and are ofthe same type are geometrically identical.

This harmonization of the interface areas at or between the componentssatisfies the requirement of reducing complexity and offers goodcost-reduction potential.

Due to the fact that the interface areas of a plurality of thecomponents that are defined in the at least two standards and are of thesame type, for example, the different pump casings of a series, aregeometrically identical, wherein the interface areas are not taken intoaccount by the standards, the individual series can be manufacturedacross standards with fewer stocked components, namely, pump casing,casing cover, bearing support assembly, shaft, impeller.

According to one configuration according to the invention, the interfacearea formed by pump casing and casing cover on contacting surfaces isgeometrically identical.

A further reduction in the number of different components can beachieved in that the interface area formed by impeller and pump casingon their interacting surfaces is geometrically identical.

The number of the plurality of components of the same type can befurther reduced if the interface area formed by impeller and casingcover on their interacting surfaces is geometrically identical.

The fact that the interface area formed by bearing support and casingcover on their interacting surfaces is geometrically identical furtherreduces the plurality of components of the same type by a multiple.

A reduction of the components of the same type is also arrived at if theinterface area formed by impeller and shaft on their contacting surfacesis geometrically identical.

The object of the invention is also achieved by a series of centrifugalpumps using a centrifugal pump described above. As a result, a series ofcentrifugal pumps is created which provides a plurality of centrifugalpumps of various sizes, of various materials and/or various applicationswith a small number of different components to be stocked.

Other objects, advantages and novel features of the present inventionwill become apparent from the following detailed description of one ormore preferred embodiments when considered in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a centrifugal pump with a casing cover clamped between thecasing and a bearing support in accordance with an embodiment of thepresent invention, and

FIG. 2 shows a centrifugal pump with a casing cover screwed onto acasing in accordance with another embodiment of the present invention.

DETAILED DESCRIPTION

FIG. 1 shows a centrifugal pump for a fluid-conducting system, whereinthe centrifugal pump has a pump casing 1 with an intake opening 2 and anoutlet opening 3. On the side of pump casing 1 opposite intake opening2, pump casing 1 has a ring- or cylinder-like opening 4 which can besealed in a fluid impervious manner by a casing cover 5. Casing cover 5adjoins a bearing surface 6 at opening 4 of pump casing 1. A projection7 is formed on bearing surface 6, which shoulder 7 partially surroundscasing cover 5 and fixes it in the radial direction. Pump casing 1 andcasing cover 4 form on their contacting surfaces a geometricallyidentical interface area 8.

A bearing support assembly 10 is fastened directly on pump casing 1 oris connected thereto by screws 9 and clamps casing cover 5 in such amanner that it sits axially and radially undisplaceably between pumpcasing 1 and bearing support assembly 10. Where necessary, for exampleif the bearing support should be thermally uncoupled from pump casing 1or from casing cover 5, bearing support assembly 10 can additionallyhave a component, not shown in FIG. 1, in particular a componentreferred to in technical language as a lantern. Casing cover 5 andbearing support assembly 10 form on their contacting surfaces aninterface area 11 which is geometrically identical.

Two bearings 12, which rotatably accommodate a shaft 13 which extendscoaxially with respect to an axis of rotation A through bearing supportassembly 10 and casing cover 5 into pump casing 1, are arranged inbearing support assembly 10. A hub 15 of an impeller 16 is placed on afirst shaft end 14, which projects into pump casing 1, of shaft 13 andis fastened securely on shaft 13 with a nut 17. As an alternative to nut17, a screw or a different fastening means can also be used to fiximpeller 16 to shaft 13. Shaft 13 and impeller 16, in particular hub 15of impeller 16, form on their contacting surfaces a geometricallyidentical interface area 18.

A motor, which drives shaft 13 in a rotary manner about axis of rotationA, is connected to a second shaft end 19, which is opposite first shaftend 14, of shaft 13.

In the area of intake opening 2 in the interior of pump casing 1, asplit ring 20 is connected by means of interference fit to pump casing1. Split ring 20 and impeller 13 are spaced apart from one another sothat a gap is formed between split ring 20 and impeller 16. Pump casing1, in particular split ring 20 of pump casing 1, and impeller 16 form ontheir interacting surfaces which form a sealing gap a geometricallyidentical interface area 21. As an alternative to this, split ring 20can also be integrated into pump casing 1. Split ring 20 can furthermorebe fastened as a race on impeller 16 and integrated into impeller 16.

Casing cover 5 has an annular portion 22 which projects into theinterior of pump casing 1 and is formed coaxially with respect to axisof rotation A, on the free end of which annular portion 22 a furthersplit ring 23 is arranged on the circumferential side, which furthersplit ring 23 is preferably also connected to casing cover 5 by means ofinterference fit. An annular portion 24 provided on impeller 16 at leastpartially surrounds annular portion 22, in particular split ring 23, ofcasing cover 5, wherein split ring 23 and impeller 13 are spaced apartfrom one another so that a gap is formed between split ring 23 andimpeller 13. Casing cover 5, in particular split ring 23 of casing cover1, and impeller 13 form on their interacting, almost contacting surfacesan interface area 25 which is geometrically identical. As an alternativeto this, split ring 23 can also be integrated into casing cover 5. It isfurthermore possible that split ring 23, like split ring 20, is arrangedor formed as a race on impeller 16.

In the case of the embodiment shown in FIG. 2, casing cover 5 whichseals opening 4 of pump casing 1 is screwed onto pump casing 1. As aresult, it is possible to connect pump casing 1 shown in FIG. 1 to asmaller bearing support assembly 10, in particular with a reduceddiameter, or vice versa, bearing support assembly 10 to a larger pumpcasing 1. The connection of bearing support assembly 10 to pump casing 1is carried out via casing cover 5, i.e. indirectly. Pump casing 1 andcasing cover 5 form on their contacting surfaces interface area 8.

Casing cover 5 in turn has one or more devices, in particular threadedholes 26, into which screws 27 can be rotated with which bearing supportassembly 10 is screwed onto casing cover 5. Other fastening means, forexample, threaded bolts, are screwed onto nuts, are also conceivable.Bearing support assembly 10 and casing cover 4 form interface area 11 ontheir contacting surfaces.

Due to the fact that interface areas 8, 11, 18, 21, 25 of a plurality ofthe components defined in the at least two standards of an identicaltype, for example, different pump casings 1 of a series, aregeometrically identical, wherein interface areas 8, 11, 18, 21, 25 arenot taken into account by the standards, the individual series can bemanufactured with fewer stocked components, namely pump casing 1, casingcover 5, bearing support assembly 10, shaft 13, impeller 16.

The foregoing disclosure has been set forth merely to illustrate theinvention and is not intended to be limiting. Since modifications of thedisclosed embodiments incorporating the spirit and substance of theinvention may occur to persons skilled in the art, the invention shouldbe construed to include everything within the scope of the appendedclaims and equivalents thereof.

LIST OF REFERENCE NUMBERS

1 Pump casing

2 Intake opening

3 Outlet opening

4 Opening

5 Casing cover

6 Bearing surface

7 Projection

8 Interface area

9 Screw

10 Bearing support assembly

11 Interface area

12 Bearing

13 Shaft

14 First shaft end

15 Hub

16 Impeller

17 Nut

18 Interface area

19 Second shaft end

20 Split ring

21 Interface area

22 Annular portion

23 Split ring

24 Annular portion

25 Interface area

26 Threaded holes

27 Screw

A Axis of rotation

1-6. (canceled)
 7. A centrifugal pump, comprising: a pump casing, a bearing support assembly connected directly or indirectly to the pump casing, a casing cover arranged between the pump casing and the bearing support assembly, a rotationally drivable shaft configured to be supported in the bearing support assembly and extend into the pump casing through the bearing support assembly and casing cover coaxially with respect to an axis of rotation of the shaft, and an impeller arranged in the pump casing and fastened on the shaft, wherein at least two of the components of the pump casing, bearing support assembly, casing cover, rotationally drivable shaft and impeller are shaped in a manner that conforms to component geometry requirements of at least one industry standard, and between-component interface areas of the at least two components which are not required by the at least one industry standard to be shaped in accordance with the component geometry requirements are shaped to interface with geometrically identical between-component interface areas of corresponding pump components shaped in a manner to conform to component geometry requirements of another industry standard.
 8. The centrifugal pump as claimed in claim 7, wherein the between-component interface areas of the pump casing and the casing cover have contacting surfaces that are geometrically complementary.
 9. The centrifugal pump as claimed in claim 7, wherein the between-component interface areas of the pump casing and the impeller have contacting surfaces that are geometrically complementary.
 10. The centrifugal pump as claimed in claim 7, wherein the between-component interface areas of the casing cover and the impeller have contacting surfaces that are geometrically complementary.
 11. The centrifugal pump as claimed in claim 8, wherein the between-component interface areas of the pump casing and the impeller have contacting surfaces that are geometrically complementary.
 12. The centrifugal pump as claimed in claim 8, wherein the between-component interface areas of the casing cover and the impeller have contacting surfaces that are geometrically complementary.
 13. The centrifugal pump as claimed in claim 9, wherein the between-component interface areas of the casing cover and the impeller have contacting surfaces that are geometrically complementary.
 14. The centrifugal pump as claimed in claim 8, wherein the between-component interface areas of the pump casing and the impeller have contacting surfaces that are geometrically complementary, and the between-component interface areas of the casing cover and the impeller have contacting surfaces that are geometrically complementary.
 15. The centrifugal pump as claimed in claim 7, wherein the between-component interface areas of the casing cover and the bearing support assembly have contacting surfaces that are geometrically complementary.
 16. The centrifugal pump as claimed in claim 7, wherein the between-component interface areas of the casing cover and the bearing support assembly have contacting surfaces that are geometrically complementary.
 17. The centrifugal pump as claimed in claim 7, wherein the between-component interface areas of the shaft and the impeller have contacting surfaces that are geometrically complementary.
 18. The centrifugal pump as claimed in claim 8, wherein the between-component interface areas of the shaft and the impeller have contacting surfaces that are geometrically complementary.
 19. The centrifugal pump as claimed in claim 9, wherein the between-component interface areas of the shaft and the impeller have contacting surfaces that are geometrically complementary.
 20. The centrifugal pump as claimed in claim 10, wherein the between-component interface areas of the shaft and the impeller have contacting surfaces that are geometrically complementary.
 21. The centrifugal pump as claimed in claim 11, wherein the between-component interface areas of the shaft and the impeller have contacting surfaces that are geometrically complementary.
 22. The centrifugal pump as claimed in claim 12, wherein the between-component interface areas of the shaft and the impeller have contacting surfaces that are geometrically complementary.
 23. The centrifugal pump as claimed in claim 13, wherein the between-component interface areas of the shaft and the impeller have contacting surfaces that are geometrically complementary.
 24. The centrifugal pump as claimed in claim 14, wherein the between-component interface areas of the shaft and the impeller have contacting surfaces that are geometrically complementary. 